JP6235282B2 - Silencer and manufacturing method thereof - Google Patents

Description

  The present invention relates to a silencer having a shell formed by welding and a method for manufacturing the silencer.

  2. Description of the Related Art Conventionally, a silencer is known in which a metal plate is formed by deep drawing press forming a metal plate, and a shell is formed by welding the metal half. For example, in the silencer of Patent Document 1, a widened portion is formed at the open ends of two bottomed cylindrical bodies formed by deep drawing press forming a metal plate, and a tip is formed at the widened portion of one bottomed cylindrical body. A tapered opening with a taper in the direction in which the tip expands outward is formed by press molding, and a tapered opening with a taper in the direction in which the tip is squeezed inward is pressed into the mouth opening of the other bottomed cylindrical body The shell is formed by laser welding the overlapped portion formed by molding and inserting and fitting the widened portion having the tapered opening portion into the widened portion having the tapered opening portion.

  Moreover, in the silencer of patent document 2, one of the two bottomed cylindrical bodies formed by deep-drawing press molding a metal plate is subjected to diameter expansion processing at the opening end portion to form a mouth expanding portion, and the other The opening of the other bottomed cylindrical body that has been reduced in diameter so as to remove the wrinkles that remain after applying the flange up while applying a wrinkle holding force to the opening end of the bottomed cylindrical body The shell is formed by inserting and fitting the end portion into the widened portion of one bottomed cylindrical body and laser welding the overlapped portion.

JP 2005-319482 A JP 2005-342756 A

  By the way, in the silencer of patent documents 1 and 2, the open end of the other metal half is inserted and fitted into the open end of one metal half, and the overlapped portion is laser welded to form a shell. Since it is formed, an extra material is required only in the overlapping region rather than the entire outer surface of the shell, which increases the material cost and the weight.

  In addition, since the overlapped portion whose back side cannot be seen is laser welded, it is difficult to easily determine that it has been reliably joined by laser welding. Furthermore, in order to securely join the overlapped portion formed by insertion fitting by laser welding, it is necessary to suppress the gap between the overlapped portions as much as possible. For this reason, there is also a problem that it takes time to adjust the production line when there is a gap and a defect occurs in the joining by laser welding.

  The present invention is proposed in view of the above-mentioned problems, and when welding a metal workpiece to form a shell, it can be easily determined that laser welding has been reliably joined, and laser welding. Silencer capable of easily adjusting the production line even when a failure occurs in the joining due to the noise, and reducing the material cost, reducing the weight, and diversifying the technology, and the manufacturing method thereof The purpose is to provide.

In the silencer of the present invention, the first processed metal product whose peripheral wall is erected from the peripheral edge of the substrate and the second processed metal product whose peripheral wall is erected from the peripheral edge of the substrate are open edges. A silencer which is abutted with each other and has a shell formed by forming a welded part over the entire circumference at the abutting portion, wherein the opening edge of the first workpiece and the second workpiece A small round portion having an arcuate cross-sectional view that is curved outward is formed at the opening edge, and the small round portion of the first workpiece and the small round portion of the second workpiece are welded. In this state, the welded portion is formed so as to be substantially flush with the outer surface in the vicinity of the first processed product and the second processed product.

According to this configuration, since the welded portion is formed at the abutting portion of the opening edge of the first processed product and the second processed product, the shell is formed by welding the metal processed product. At this time, it is possible to easily determine that the laser welding is reliably performed, and it is possible to easily adjust the production line even when a problem occurs in the laser welding. Further, since there is no need to provide an overlapping portion at the opening end, an extra material used for the region of the overlapping portion is not necessary, and material cost and weight can be reduced. In addition, the shell can be formed by laser welding the first processed product and the second processed product with a novel configuration completely different from the existing technology, and the technology can be diversified. In addition, by making the opening edge to be joined for welding a small rounded portion, it is possible to absorb the size error and to make a match even when the size varies. Further, when the opening edge is abutted by the small rounded portion, it is possible to prevent a portion where the vicinity of the opening edge is bent and does not abut, and a stable abutting can be performed. Further, by making the welded portion substantially flush with the outer surfaces in the vicinity of the first and second processed products, the installation space required when the welded portion is provided in an extended manner can be eliminated. The advantage of being able to further reduce the weight and reducing the under-floor air resistance is also obtained.

In the silencer of the present invention, widened portions are formed at the open end of the first processed product and the open end of the second processed product, respectively, and the leading edge of each widened portion is the open end. It is characterized by an edge.
According to this configuration, the dimensional accuracy of the opening edge to be abutted can be improved by forming the widened portion by press molding or the like on both the first and second processed products.

The method for manufacturing a silencer of the present invention has a small round- shaped portion having a cross-sectional arc shape in which a peripheral wall is erected from a peripheral end of a substrate and curved outward at an opening edge by performing press molding on at least a metal plate. A first step of forming a first processed product, and a second processed product having a small rounded portion having a circular arc-shaped cross-sectional view, the peripheral wall standing from the peripheral edge of the substrate and curved outward at the opening edge; A second step of mutually butting the small rounded portion of the opening edge of the first workpiece and the small rounded portion of the opening edge of the second workpiece, and the entire circumference from the outer periphery to the butted portion The shell is formed by forming a welded portion that is substantially flush with the outer surface in the vicinity of the first processed product and the second processed product by performing laser welding over the surface and melting the small rounded portion by laser welding. And a third step of forming.
According to this configuration, since the welded portion is formed at the abutting portion of the opening edge of the first processed product and the second processed product, the shell is formed by welding the metal processed product. At this time, it is possible to easily determine that the laser welding is reliably performed, and it is possible to easily adjust the production line even when a problem occurs in the laser welding. Further, since there is no need to provide an overlapping portion at the opening end, an extra material used for the region of the overlapping portion is not necessary, and material cost and weight can be reduced. In addition, the shell can be formed by laser welding the first processed product and the second processed product with a novel configuration completely different from the existing technology, and the technology can be diversified. In addition, by making the opening edge to be joined for welding a small rounded portion, it is possible to absorb the size error and to make a match even when the size varies. Further, when the opening edge is abutted by the small rounded portion, it is possible to prevent a portion where the vicinity of the opening edge is bent and does not abut, and a stable abutting can be performed. Further, by making the welded portion substantially flush with the outer surfaces in the vicinity of the first and second processed products, the installation space required when the welded portion is provided in an extended manner can be eliminated. The advantage of being able to further reduce the weight and reducing the under-floor air resistance is also obtained.

The silencer manufacturing method of the present invention is characterized in that, in the first step, the widened portion is formed at the opening end, and the small rounded portion is formed at the tip edge of the widened portion. 1 processed product and the second processed product are formed, and in the second step, the root of the widened portion of the first processed product and the root of the widened portion of the second processed product are The small rounded portions are butted together so as to be held, and in the third step, the welded portion is formed by performing the laser welding in the butted state with the small rounded portion held by the root holding. .
According to this configuration, the dimensional accuracy of the opening edge to be abutted can be improved by forming the widened portion by press molding or the like on both the first and second processed products. Moreover, advanced positioning can be stably performed by holding and positioning the base of the widened portion.

In the silencer manufacturing method of the present invention, in the first step, the widened portion is formed from an overhanging portion protruding outward and a peripheral wall that is bent substantially perpendicularly from the overhanging portion and extends in the abutting direction. And in the said 2nd process, the said small radius part is mutually butt | matched so that the said overhang | projection part may be pressed in the butt | matching direction, It is characterized by the above-mentioned.
According to this configuration, the overhanging portion can be pressed in the abutting direction, and a force along the abutting direction can be stably applied to the peripheral wall of the widened portion, and the opening edge of the first workpiece and the second The opening edge of the processed product can be abutted more accurately and stably.

In the method for manufacturing a silencer of the present invention, in the second step, the radius of the small rounded portion of the first processed product and the small rounded portion of the second processed product is pressed in the abutting direction so as to be small. And in the third step, laser welding is performed on the abutting portion in an abutting state in which the radius of the small radius portion of the first workpiece and the small radius portion of the second workpiece is small. To do.
According to this, it is possible to secure a larger joint portion between the first processed product and the second processed product, to improve the stability of the welding process, and to break or erode near the inner end of the joint portion. It is possible to eliminate or suppress the formation of a notch that causes the above-mentioned factors, and to improve the welding strength and the corrosion resistance.

  According to the present invention, when a metal workpiece is welded to form a shell, it can be easily determined that laser welding has been securely joined, and there has been a problem in joining by laser welding. In addition, it is possible to easily adjust the production line, reduce material costs, reduce weight, and diversify technologies.

The perspective view which shows the silencer of embodiment. The side view which shows the shell of the silencer of embodiment. The fragmentary sectional view showing the circumference of the welding part of the shell in the silencer of an embodiment. (A)-(c) is a fragmentary sectional view which shows the opening edge part periphery in each manufacturing step of an upper half body. (A)-(c) is a fragmentary sectional view which shows the opening edge part periphery in each manufacturing step of a lower half body. (A) is a partial cross-sectional explanatory view around the opening end portion explaining the abutment of the upper half body and the lower half body, (b) is a partial cross section around the opening end portion of the upper half body and the lower half body in the abutting state Illustration. (A) is a partial cross-sectional explanatory view around the opening end portion explaining the abutment of the upper half body and the lower half body, (b) is a periphery of the opening end portion of the upper half body and the lower half body in the abutting state of the modified example FIG. (A) is a fragmentary sectional view showing the periphery of the opening end of the shell in the silencer of the modification, and (b) is a partial sectional view showing the periphery of the opening end of the shell in the silencer of another modification.

[Muffler of the embodiment and manufacturing method thereof]
As shown in FIGS. 1 and 2, the silencer 1 of the present embodiment includes a shell 2, and the shell 2 is a substantially rectangular box-shaped upper half 3 that is a metal processed product, and a substantially rectangular box. The lower half 4 which is a metal work product in shape is abutted at the opening edge and welded at the abutting location.

  As shown in FIGS. 1 to 3, the upper half 3 has a substrate 31 and a peripheral wall 32 standing substantially vertically from the peripheral end of the substrate 31, and a widened portion 33 at the opening end of the peripheral wall 32. Is formed. The widened portion 33 has a protruding portion 331 that is bent from the peripheral wall 32 and protrudes outward. In the illustrated example, the protruding portion 33 extends substantially horizontally so as to be bent from the peripheral wall 32 at a substantially right angle. 331 is formed. Further, a peripheral wall 332 is formed so as to be bent at a substantially right angle from the tip of the overhang portion 331 and extend substantially vertically, and the widened portion 33 is composed of an overhang portion 331 and a peripheral wall 332.

  As shown in FIGS. 1 to 3, the lower half 4 has a substrate 41 and a peripheral wall 42 standing substantially perpendicularly from the peripheral end of the substrate 41, and a widened portion at the opening end of the peripheral wall 42. 43 is formed. The widened portion 43 has a protruding portion 431 that is bent from the peripheral wall 42 and protrudes outward. In the illustrated example, the protruding portion 43 extends substantially horizontally so as to be bent at a substantially right angle from the peripheral wall 42. 431 is formed. Further, a peripheral wall 432 is formed so as to be bent substantially perpendicularly from the tip of the overhang portion 431 and extend substantially vertically, and the widened portion 43 is composed of the overhang portion 431 and the peripheral wall 432.

  The inner and outer dimensions of the peripheral wall 332 of the widened portion 33 of the upper half 3 are formed to correspond to the inner and outer dimensions of the peripheral wall 432 of the widened portion 43 of the lower half 4, respectively. The leading edge of the peripheral wall 332, which is the opening edge of the upper half 3, and the leading edge of the peripheral wall 432, which is the opening edge of the lower half 4, are abutted with each other, and a circumferential lip spreads at the abutting portion. Laser welding is performed over the entire circumference along the portions 33 and 43, and a welded portion 5 is formed by laser welding.

  The weld 5 is formed to be substantially flush with the outer surfaces of the peripheral wall 332 and the peripheral wall 432. In addition, the substantially flush range from the outer surface in the present invention means that the protruding amount from the outer surface of the peripheral wall to be abutted such as the peripheral walls 332 and 432 where the welded portion 5 is formed is within 3.0 mm or less. doing.

  Further, through holes 45, 46 are formed in opposing side walls of the peripheral wall 42 of the lower half 4, and the silencer is provided by providing the inlet pipe 6 and the outlet pipe 7 so as to be inserted into the through holes 45, 46. 1 is configured.

  When forming the shell 2 in the manufacturing process of the silencer 1 of the present embodiment, for example, the first half that becomes the upper half 3 is formed by deep drawing press forming a flat metal plate using a die and a punch. Intermediate processed product 30a is formed. The first intermediate processed product 30a includes a substrate 31, a peripheral wall 32a erected in a substantially vertical direction with respect to the substrate 31, and an intermediate processed flange 34a that is bent at a substantially right angle from the upper end edge of the peripheral wall 32a to the outer periphery. (See FIG. 4A).

  Thereafter, the first intermediate processed product 30a is press-molded at the opening end of the first intermediate processed product 30a using another stepped die and a punch having a larger outer dimension than the previous step, so that the peripheral wall 32 can be removed. An intermediate working flange shorter than the intermediate working flange 34a is formed at the same time as forming the widened portion 33 composed of a bent portion 331 and a peripheral wall 332 bent substantially at right angles from the protruding portion 331 and extending in the abutting direction. 34b and the peripheral wall 32 whose height is lower than the peripheral wall 32a by the height of the widened portion 33 is formed to obtain a first intermediate workpiece 30b (see FIG. 4B). Incidentally, the transition of the intermediate shape from the flat metal plate to the first intermediate processed product 30b by press molding is appropriate in addition to this example.

  Thereafter, the first intermediate processed product 30b is cut by press molding or the like while leaving a part of the intermediate processed flange 34b, thereby removing the cut portion C1 and forming the small rounded portion 34 at the leading edge of the peripheral wall 332. The upper half 3 is obtained. In other words, the upper half 3 that is the first processed product is a small portion that curves outwardly before the welded portion 5 is formed by laser welding to the abutting portion with the lower half 4. The rounded portion 34 is formed (see FIG. 4C). Further, by forming the small round portion 34, the peripheral wall 332 is urged inward and stabilized in a shape extending substantially vertically, and more accurate and stable abutment is possible in a later-described abutment.

  The small round portion 34 is melted by laser welding, which will be described later, and is formed with an amount of protrusion outward from the peripheral wall 332 within 3.0 mm in order to form a weld portion 5 that is substantially flush with the peripheral walls 332 and 432. It is also preferable that the small round portion 44 described later is similarly formed so that the protruding amount outward from the peripheral wall 432 is within 3.0 mm. Moreover, it is preferable that the length to the abutting direction of the small round parts 34 and 44 shall be 3.0 mm or less.

  Moreover, when forming the lower half 4 which is a 2nd processed product, it forms in the process similar to the process of forming the upper half 3 which is a 1st processed product, for example. That is, by performing deep drawing press molding of a flat metal plate using a die and a punch, the peripheral wall 42a standing upright in a direction substantially perpendicular to the substrate 41, and the upper end edge of the peripheral wall 42a from the upper edge to the outer periphery. A second intermediate processed product 40a having an intermediate processed flange 44a bent at a substantially right angle is formed (see FIG. 5A).

  Thereafter, the second intermediate workpiece 40a is press-formed at the opening end of the second intermediate workpiece 40a using another stepped die and a punch having a larger outer dimension than the previous step, whereby a protruding portion 431 bent from the peripheral wall 42 is formed. At the same time as forming a flared portion 43 composed of a peripheral wall 432 bent substantially at right angles from the overhanging portion 431 and extending in the abutting direction, an intermediate processed flange 44b shorter than the intermediate processed flange 44a, and a flared portion longer than the peripheral wall 42a A peripheral wall 42 having a height reduced by 43 is formed to obtain a second intermediate workpiece 40b (see FIG. 5B). As in the case of the first intermediate processed product 30b, the transition of the intermediate shape from the flat metal plate to the second intermediate processed product 40b by press molding is appropriate in addition to this example.

  Thereafter, by cutting with press molding or the like while leaving a part of the intermediate working flange 44b, the cut portion C2 is removed to form a small rounded portion 44 at the leading edge of the peripheral wall 432, and the lower half 4 is obtained. That is, in the stage before the welded part 5 is formed by welding the lower half 4 that is the second processed product to the abutting portion with the upper half 3 by laser welding, the small part that curves outwardly is formed. The rounded portion 44 is formed (see FIG. 5C). Further, by forming the small rounded portion 44, the peripheral wall 432 is urged inward and stabilized in a shape extending substantially vertically, and more accurate and stable abutment is possible in the abutment described later.

  When the depth of the upper half 3 and the lower half 4 is relatively shallow, etc., the steps of FIGS. 4A and 4B or FIGS. 5A and 5B are performed once by press molding. The first and second intermediate workpieces 30b and 40b can be formed from the metal plate without passing through the first and second intermediate workpieces 30a and 40a. It is also possible to form the upper half 3 and the lower half 4 of FIGS. 4C and 5C only by deep drawing press forming from a metal plate without cutting the cut portions C1 and C2. However, it is preferable to use a step of cutting the cut portions C1 and C2 as described above from the point of obtaining a high quality shape by surely removing wrinkles generated by press molding.

  Next, as shown in FIG. 6A, a holder 101 is provided so as to make surface contact with the substrate 31, the peripheral wall 32, and the overhang portion 331 of the upper half 3, and the upper half 3 is held by the holder 101. Accordingly, the holding tool 102 is provided so as to hold the base of the widened portion 33 of the upper half 3 and to come into surface contact with the substrate 41, the peripheral wall 42, and the overhanging portion 431 of the lower half 4. By holding the lower half 4 in this way, the base of the widened portion 43 of the lower half 4 is held, and the upper half 3 and the lower half 4 are brought closer to each other in this holding state, as shown in FIG. As shown in b), the overhanging portions 331 and 431 are pressed in the abutting direction by the holding tools 101 and 102 so that the small rounded portion 34 at the opening edge of the upper half 3 and the opening of the lower half 4 The small rounded portion 44 at the end is abutted against each other.

  Then, with the holders 101 and 102 holding the bases of the upper half 3 and the lower half 4 and abutting the small round portions 34 and 44, laser welding is performed on the abutting portion from the outer circumference to the entire circumference. (Refer to FIG. 6B). By melting the small round portions 34 and 44 by laser welding, the peripheral walls 332 and 432 corresponding to the outer surfaces in the vicinity of the welded portion 5 of the upper half 3 and the lower half 4 in this example. A substantially flat weld portion 5 is formed, and the shell 2 formed with the weld portion 5 shown in FIG. 3 is completed.

  In this step of pressing and abutting and welding, as shown in FIG. 7, the radius before the abutting of the small radius portions 34 and 44 is reduced by pressing and abutting, and the radius is reduced. It is more preferable to perform welding in the state of the rounded portions 33 and 44. As a result, it is possible to secure a larger mating portion SF and improve the stability of the welding process, and to eliminate the formation of notches that cause breakage and erosion in the vicinity of the inner end portion of the mating portion SF. Alternatively, it is possible to suppress the welding strength and the corrosion resistance.

In the case where the radius before the abutting of the small round portions 34 and 44 is pressed and reduced, the small round portions 33 and 34 having a radius of about 2.5 to 3.0 mm in the abutting direction before the abutting, for example. However, it is preferable to compress and deform so that the length in the abutting direction is about 0.5 to 2.0 mm, more preferably about 0.5 to 1.5 mm by the pressing and abutting process.

  According to the present embodiment, since the welded portion 5 is formed at the abutting portion of the opening edge of the upper half 3 and the lower half 4 that can be seen, the upper half 3 and the lower half 4 are welded together. Thus, when forming the shell 2, it can be easily determined that the laser welding is reliably performed, and the adjustment of the production line can be easily performed even when a failure occurs in the laser welding. It becomes possible. Further, since there is no need to provide an overlapping portion at the opening end, an extra material used for the region of the overlapping portion is not necessary, and material cost and weight can be reduced. In addition, the shell 2 can be formed by laser welding the upper half 3 and the lower half 4 with a novel configuration that is completely different from the existing technology, and the technology can be diversified.

  In addition, by forming the widened portions 33 and 43 in both the upper half 3 and the lower half 4 by press molding, the dimensional accuracy of the opening edge to be abutted can be improved. Moreover, the overhang | projection parts 331 and 431 which are the level | step differences with the holders 101 and 102 are pressed in the abutting direction, and the force along the abutting direction is stably applied to the surrounding walls 331 and 431 of the widened parts 33 and 43. The opening edge of the upper half 3 and the opening edge of the lower half 4 can be more accurately and stably abutted.

  In addition, by setting the opening edge to be abutted for welding to the small rounded portions 34 and 44, it is possible to abut the abutting by absorbing a dimensional error even when the dimension varies. Further, when the opening edge is abutted by the small rounded portions 34 and 44, it is possible to prevent a portion where the vicinity of the opening edge is bent and does not abut, and stable abutting can be performed. Further, by making the welded portion 5 substantially flush with the outer surfaces in the vicinity of the upper half 3 and the lower half 4, it is possible to eliminate the installation space required when the welded portion 5 is provided in an overhanging manner. Moreover, the advantage that the weight of the silencer 1 can be further reduced and the air resistance under the floor can be reduced is also obtained.

[Modifications of Embodiment, etc.]
In addition to the configurations of the inventions and embodiments, the invention disclosed in the present specification is specified by changing these partial configurations to other configurations disclosed in the present specification within the applicable range, or these To which the other configurations disclosed in the present specification are added or specified, or those partial configurations are deleted and specified to the extent that partial effects can be obtained. The following modifications are also included.

  For example, the shell 2 in the above-described embodiment is configured such that the upper half 3 and the lower half 4 are vertically butted. However, in the present invention, a metal work product in which a peripheral wall is erected from the peripheral edge of the substrate is used. Appropriate configurations including a shell in which the ends are butted against each other at the opening edge and laser welding is performed over the entire circumference to form a welded portion are included. Further, a configuration in which the halves which are the first and second processed products are butted together and the butted portions are welded is also included.

  The through-holes through which the inlet pipe 6 and the outlet pipe 7 are inserted can be provided at appropriate positions within the scope of the present invention. For example, both of the through-holes through which the inlet pipe 6 and the outlet pipe 7 are inserted. Can be formed in the upper half 3, or one of the through holes can be formed in the upper half 3 and the other through hole can be formed in the lower half 4.

  Moreover, the board | substrates 31 and 41 of the upper half 3 and the lower half 4 are not limited to a flat thing, For example, an appropriate plate-like thing is included, For example, it is good also as a thing with the shape where the center was dented. Further, the peripheral walls 32 and 42 erected from the substrates 31 and 41 are not limited to those erected in a substantially vertical direction, but are suitably erected in a tapered shape so as to expand toward the opening, for example.

  In the above embodiment, the small rounded portions 34 and 44 are formed on the opening edge of the widened portion 33 of the upper half 3 and the open edge of the widened portion 43 of the lower half 4, respectively. However, the present invention is not limited to such a configuration. For example, as shown in FIG. 8A, the widened portions 33m and 43m of the upper half 3m and the lower half 4m The peripheral walls 332m and 432m have a shape extending substantially vertically without the small rounded portions 34 and 44, the opening edges of the peripheral walls 332m and 432m abut each other, and a welded portion 5m is formed by laser welding at the abutting portion. It is also possible to adopt a configuration.

  Moreover, it is also possible to make it the structure which does not form the flared parts 33 and 43, for example, as shown in FIG.8 (b), a small round part is formed in the opening edge of the surrounding wall 32n of the upper half 3n, It is also possible to form a small rounded portion at the opening edge of the peripheral wall 42n of the lower half 4n, abut the small rounded portions to each other, and form a welded portion 5n by laser welding at the joined portion. .

  Further, the peripheral wall 32n of the upper half 3n and the peripheral wall 42n of the lower half 4n are formed in a substantially vertically extending shape where no small rounded portion is formed, and the opening edges of the peripheral walls 32n and 42n are mutually butted. It is also possible to form a welded portion 5n by laser welding at the abutting portion.

  INDUSTRIAL APPLICABILITY The present invention can be used in automobile silencers and manufacturing processes thereof.

DESCRIPTION OF SYMBOLS 1 ... Silencer 2 ... Shell 3, 3m, 3n ... Upper half body 30a, 30b ... 1st intermediate processed product 31 ... Substrate 32, 32a, 32n ... Peripheral wall 33 ... Widening part 331 ... Overhang part 332, 332m ... Peripheral wall 34 ... Small round portion 34a, 34b ... Intermediate processing flange 4,4m, 4n ... Lower half 40a, 40b ... Second intermediate processed product 41 ... Substrate 42, 42a, 42n ... Peripheral wall 43 ... Expanded portion 431 ... Overhang part 432, 432m ... peripheral wall 44 ... small round part 44a, 44b ... intermediate processing flange 45, 46 ... through hole 5, 5m, 5n ... welded part 6 ... inlet pipe 7 ... outlet pipe 101, 102 ... holder C1, C2 ... Cut part SF ... Matching part

Claims (6)

A metal first processed product whose peripheral wall is erected from the peripheral edge of the substrate and a metal second processed product whose peripheral wall is erected from the peripheral end of the substrate are abutted against each other at the opening edge. A silencer in which a weld is formed around the entire circumference and a shell is formed.
A small arcuate portion having a cross-sectional arc shape that curves outwardly is formed at each of the opening edge of the first workpiece and the opening edge of the second workpiece,
In the state where the small rounded portion of the first processed product and the small rounded portion of the second processed product are welded, an outer surface and a substantially surface in the vicinity of the first processed product and the second processed product. A muffler characterized in that a single weld is formed.   A widened portion is formed at each of the open end of the first processed product and the open end of the second processed product, and the leading edge of each of the widened portions is the open end edge. The silencer according to claim 1, wherein At least a metal plate is press-molded to form a first processed product having a small rounded portion with an arcuate cross-sectional shape in which a peripheral wall is erected from the peripheral edge of the substrate and curved outward at the opening edge, A first step of forming a second workpiece having a small rounded portion having an arcuate cross-sectional shape in which a peripheral wall is erected from an end and curved outward at an opening edge;
A second step of butting the small rounded portion of the opening edge of the first workpiece and the small rounded portion of the opening edge of the second workpiece;
Laser welding is performed on the abutting portion from the outer periphery to the entire periphery, and the small rounded portion is melted by laser welding, so that the welding is substantially flush with the outer surfaces in the vicinity of the first processed product and the second processed product. A third step of forming a shell by forming a portion;
A method of manufacturing a silencer, comprising: In the first step, a widened portion is formed at an opening end, and the small rounded portion is formed at a leading edge of the widened portion, so that the first processed product and the second processed product are formed. Forming goods,
In the second step, the small rounded portions are butted against each other so as to hold the base of the widened portion of the first processed product and the base of the widened portion of the second processed product,
The method for manufacturing a silencer according to claim 3, wherein, in the third step, the laser welding is performed in a state where the small rounded portion by the root holding is abutted to form the welded portion. In the first step, the widened portion is formed from a projecting portion that protrudes outward and a peripheral wall that is bent substantially perpendicularly from the projecting portion and extends in the abutting direction,
5. The method for manufacturing a silencer according to claim 4, wherein in the second step, the small rounded portions are butted together so as to press the overhanging portion in the butting direction. In the second step, the butt is pressed in the butt direction so as to reduce the radius of the small rounded portion of the first workpiece and the small rounded portion of the second workpiece,
In the third step, laser welding is performed on the abutting portion in a butting state in which the radius of the small radius portion of the first workpiece and the small radius portion of the second workpiece is small. The manufacturing method of the silencer in any one of 3-5.

Images